Point of
no return: a hellish ‘hothouse Earth’ getting closer, scientists say
Continued
global heating could set irreversible course by triggering climate tipping
points, but most people unaware
Damian
Carrington Environment editor
Wed 11
Feb 2026 16.00 GMT
The world
is closer than thought to a “point of no return” after which runaway global
heating cannot be stopped, scientists have said.
Continued
global heating could trigger climate tipping points, leading to a cascade of
further tipping points and feedback loops, they said. This would lock the world
into a new and hellish “hothouse Earth” climate far worse than the 2-3C
temperature rise the world is on track to reach. The climate would also be very
different to the benign conditions of the past 11,000 years, during which the
whole of human civilisation developed.
At just
1.3C of global heating in recent years, extreme weather is already taking lives
and destroying livelihoods across the globe. At 3-4C, “the economy and society
will cease to function as we know it”, scientists said last week, but a
hothouse Earth would be even more fiery.
The
public and politicians were largely unaware of the risk of passing the point of
no return, the researchers said. The group said they were issuing their warning
because while rapid and immediate cuts to fossil fuel burning were challenging,
reversing course was likely to be impossible once on the path to a hothouse
Earth, even if emissions were eventually slashed.
It was
difficult to predict when climate tipping points would be triggered, making
precaution vital, said Dr Christopher Wolf, a scientist at Terrestrial
Ecosystems Research Associates in the US. Wolf is a member of a study team that
includes Prof Johan Rockström at the Potsdam Institute for Climate Impact
Research in Germany and Prof Hans Joachim Schellnhuber at the International
Institute for Applied Systems Analysis in Austria.
“Crossing
even some of the thresholds could commit the planet to a hothouse trajectory,”
said Wolf. “Policymakers and the public remain largely unaware of the risks
posed by what would effectively be a point-of-no-return transition.
“It’s
likely that global temperatures are [already] as warm as, or warmer than, at
any point in the last 125,000 years and that climate change is advancing faster
than many scientists predicted.”
It is
also likely that carbon dioxide levels are the highest they have been in at
least 2m years.
Prof Tim
Lenton, an expert on tipping points at the University of Exeter in the UK,
said: “We know we are running profound risks on the current climate trajectory,
which we can’t rule out could turn into a trajectory towards a much less
habitable state of the climate for us. However, we don’t need to be heading
towards a hothouse Earth for there to be profound risks to humanity and our
societies – these will already be upon us if we continue to 3C global warming.”
The
assessment, which was published in the journal One Earth, synthesised recent
scientific findings on climate feedback loops and 16 tipping elements. The
tipping elements include the Greenland and Antarctic ice sheets, mountain
glaciers, polar sea ice, sub-Arctic forests and permafrost, the Amazon
rainforest and the Atlantic meridional overturning circulation (Amoc), a system
of ocean currents that strongly influences the global climate.
Tipping
may already be happening in Greenland and west Antarctica, with permafrost,
mountain glaciers and the Amazon rainforest appearing to be on the verge, the
scientists said.
“Research
shows that several Earth system components may be closer to destabilising than
once believed,” they concluded. “While the exact risk is uncertain, it is clear
that current climate [action] commitments are insufficient.”
Prof
William Ripple, at Oregon State University, US, who led the analysis, said:
“The Amoc is already showing signs of weakening, and this could increase the
risk of Amazon dieback. Carbon released by an Amazon dieback would further
amplify global warming and interact with other feedback loops. We need to act
quickly on our rapidly dwindling opportunities to prevent dangerous and
unmanageable climate outcomes.”
Scientists
warned in 2018 of the prospect of a hothouse Earth. In this scenario, global
temperature stays significantly above the 4C rise of current worst-case climate
scenarios for thousands of years, driving a huge rise in sea level that drowns
coastal cities. The scientists said then that the “impacts of a hothouse Earth
pathway on human societies would likely be massive, sometimes abrupt, and
undoubtedly disruptive”.

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